In order to crack the nutshell and retrieve the meat therefrom, nutcrackers have been developed that allow both a small degree of automatic adjustment for the size of a particular nut and application of the crushing force over only a predetermined distance to prevent shattering of the nutshell into many small fragments. In limiting the travel, application of excessive force is prevented. However, these nutcrackers require a number of maneuvers to place the nut within the jaws and then crack the nutshell itself. For example, in U.S. Pat. No. 3,477,487 issued to S. H. Holt, a nutcracker is disclosed that has a spring-adjusted jaw and a rotational lever on the other jaw. The spring-adjusted jaw provides compensation for the size of the nut and the rotational jaw provides the predetermined cracking force which is provided by advancing the jaw a predetermined distance. To crack the nut, the adjusting jaw must be manually opened and then released on the nut. The rotating lever is then operated to crack the nut. In another example, U.S. Pat. No. 3,159,194 issued to W. A. Anderson, a nutcracker is disclosed that has a series of levers and ratchet-type mechanisms to advance the jaws toward each other. This mechanism also provides a degree of size compensation for the nut itself in addition to the predetermining amount of travel.
The above-discussed nutcrackers illustrate examples of prior art nutcrackers that provide for some degree of size compensation and limited cracking of the nut. However, they are overly complicated and require a number of moving parts. In view of this, it is desirable to provide a nutcracker that automatically compensates for the size of the nut and delivers the cracking force over a predetermined distance with a minimum number of parts.